[mdx] what do do about duplicates

[Leif Johansson]

So now that we got through the trust-thread (try saying that quickly 3 times) 
I've got another one for you all:

What is the aggregator to do if it receives different metadata for the same
entityID from 2 different sources?

- Throw some or all of it away?
- Signal an error and have a human deal with it?
- Merge metadata?
- Keept the metadata separate and use the trust engine to figure out which to 
expose in published aggregates?

And by the way: what constitutes difference in metadata?

	Cheers Leif